Algorithm research of fuzzy-PID parameters self-tuning wall thickness controller

The working principle of hollow blow-molding machine is introduced: Raw material plasticization, injection, blowing, cooling and molding; In order to assure product strength and raw materials conserving, it has analyzed the significance of domestic wall thickness controller with advanced performance. Meanwhile, the algorithm of wall thickness controller is specifically demonstrated in this paper for the purpose of promoting its working capability and realizing rapid and accurate tracing of the wall thickness controller. On the basis of general design of fuzzy PID parameter self-tuning controller, an improved fuzzy controller is presented. Its structure is altered to "two inputs one output" from "two inputs three outputs", which has simplified the calculation process. Moreover, look-up table method has been replaced by weight function method in the fuzzy logical reasoning rule, which has prevented the high deviation of system stability. The test indicates that the improved controller has the characteristics of simple software design, high controlling accuracy and good system dynamic performances.